The present invention relates to an image processing apparatus having a function to avoid malfunction during program write for program change or version upgrade.
Conventionally, there have been known such image processing apparatus as copying machines and printers that accept program rewrite for program change or version upgrade. One example is shown in Japanese Patent Laid-Open Publication No. 10-213997, where when program rewrite is performed by connecting an IC card-type external storage means to the device, power supply to loads for image forming (such as a fixing heater and a drive motor) is stopped to avoid malfunction. Another example is shown in Japanese Patent Laid-Open Publication No. 8-76654, where when downloading program in a memory, a master CPU notifies a slave CPU of the state of rewriting, and power supply to loads are controlled to be stopped by the slave CPU.
However, in the apparatus according to the above-stated Japanese Patent Laid-Open Publication No. 10-213997, power supply to loads is unconditionally stopped when the external storage means is connected, which may generate unnecessary loss time and thereby affect sufficiency of the apparatus. In the apparatus according to the above-stated Japanese Patent Laid-Open Publication No. 8-76654, necessity of two control devices (master CPU and slave CPU) complicates apparatus configuration, and absence of backup about whether or not program rewrite is under proceeding degrades operational reliability during program rewrite.